Forget the Jets and the Sharks, the Yankees and the Red Sox, or Arsenal v. Spurs (on my side of the pond). Few rivalries run as deep as Coca-Cola and Pepsi.

That explains why Madison Avenue was so stunned by last week’s news: Publicis Groupe had won PepsiCo’s $1.7 billion global media, data, and tech account without a traditional pitch. (Omnicom was Pepsi’s global media partner for more than 25 years, though Publicis media agencies did already work with the beverage and snacks giant in some markets in Asia.)

The context: Publicis handles Coca-Cola’s media in North America — and was competing against incumbent WPP for Coke’s global business.

“I…